Attachment of heads to bellows



Aug. 1932. J. v. GIESLER ATTACHMENT OF HEADS' TO BELLOWS Filed Aug. 2, 1930 gmmm WW.MW EMW Patented Aug. 9, 1932 UNITED STATES PATENT OFFICE? JEAN V. GIESLER, OF KNOXVILLE, TENNESSEE, ASSIGNOR TO THE FULTON SYLEHON COMPANY, OF KNOXVILLE, TENNESSEE, A CORFORATION OF DELAWARE ATTACHMENT OF HEADS TO IBELLOWS Application filed August 2, 1930. Serial 1T0. 472,565.

This invention relates to the art of manufacturing flexible metal bellows and more particularly to the attachment of a .head or heads thereto.

Flexible metal bellows are ordinarily manufactured by forming relatively deep corrugations in tubular blanks of relatively thin metal, on the order of .010" in thickness. The blank may take the form of a 10 drawn tube having a closed integral end formed b bending a fiat blank into a cylinformed by cupping and drawing a metal disk, or it may take the form of an open ended tube, whether formed integrally by drawing or other suitable operations or der and oining the meeting edges. In the former case, wherein the blank has one end closed by an integral head, an enclosed vessel may be formed by securing a head in the open end of the tubular wall before, during or after corrugating, while in the latter case, wherein the blank is an open ended tube, an enclosed vessel may be formed by securing heads in both ends of the tubular wall before,

during or after corrugating. In either event,

considerable difficulty has heretofore been experienced in obtaining a strong, permanent, hermetically-sealedjoint between the lateral wall and the head, because of the thinness of the metal of the lateral wall, and also considerable difiiculty has been encountered in attaching such relatively thin metal to a relatively stiif thick head without injury to the metal of the lateral wall.

Moreover, if the head is to be attached to the lateral wall after the relatively deep corrugations are formed, extreme care must be observed in preventing injury to the corrugations during the attachment of the head. The operations employed in forming the relatively deep corrugations are such as to predeterminately work the metal so as to impart toughness and temper thereto, and any subsequent operation which may impair the toughness or temper of the corrugations contiguous to the head or heads will impair the durability or resilience of the bellows as a unit.

On the other hand, when the relatively deep corrugations are to be formed by fluid pressure, it is frequently desirable to attach the head or heads to the tube in advance of subjecting the tube to the pressures employed in producing the corrugations. The pressures employed in corrugating the blank may be relatively high and a joint which is capable of withstanding the pressures encountered by the bellows in service may be incapable of withstanding the pressures encountered in corrugating the blank. At the same time, the attachment of the head or heads to the blank in advance of the corrugating operation possesses the advantage that the corrugating operation will expose any leak in the joint between the head and the lateral wall and save the loss and expense that may arise from installing a bellows with a defective joint between the head and lateral wall.

It has heretofore been the practice to solder or braze the head to the lateral wall, but the use of soft solder requires extreme care because the soldering fluid may get onto the relatively delicate metal of the flexible lateral wall and seriously impair its durability. To minimize this danger more or less complicated and expensive constructions have been suggested, but these add to the cost of production and do not entirely assure that the thin metal of the lateral wall has not been injured. Efl'orts have also been made to employ more or less complicated mechanical seams, to employ casting in the attachment of a head to the lateral wall, and various other expedients.

Additionally, it is frequently desirable that the head subserve the function of a backing for the contiguous corrugation of the lateral wall. This is particularly true where relatively high pressures are employed and a relatively stifl' rigid head is desirable for the purpose of backing and preventing distortion of the end corrugation.

' It is an object of this invention to provide a method of attaching a head to a lateral wall which is available for use whether the head is attached to the blank before treatment of the lateral wall, or whether the head is attached at an intermediate stage of the corrugating operations, or whether the head is attached after the corrugating operations have been completed, and to facilitate the description and definition of the invention the term bellows tube will be used to designate the lateral wall to which a head is to be attached whether the lateral wall'is c indrical, as in the case of the original blank, or has partly formed corrugations therein, or has been com-. pletely corrugated into a bellows.

Another object of this invention is to provide a method .of attaching a head to a 'bellows tube which is equally available for securing a head to the open end of a blank having an integral head at its opposite end, or in securing a head to either or both ends of an open-ended blank, and to facilitate the description and definition of the invention the reference to the attachment of a head to a bellows tube is to be understood as embracing the attachment of a head to the open end of a blank having a closed end or to either or both ends of an open-ended blank.

Another object of this invention is to provide a method of attaching a head to a bellows tube which is of such character that the thereto by a seam thin metal of'the lateral wall is not injured whether in cylindrical or corrugated form, and of such a character that when the method is used in attaching a head to a corrugated tube the toughness and temper of the formed corrugations are not impaired.

Another object of this invention is to provide a method of attaching a head to a bellows tube which efl'ects a joint of such strength that the joint will withstand the pressures encountered in forming the corrugations by fluid pressure.

Another object of this invention is to provide method of attaching a head to a bellows tube which avoids the complications and expense of production characteristics of mechanical joints heretofore suggested and which avoids the use of soft solder and the difliculties heretofore experienced with the use of the same.

Another object of this invention is to provide a method of attaching a head to a bellows tube which is available for use with heads that are also adapted to act as backings for the contiguous corrugations of the formed bellows.

Another object of this invention is to provide a method of attaching a head to abellows tube which is simple in character and easy to 1perform, which does not requ re the use of ighly skilled labor or complicated equipment, and which is adapted to produce a strong, permanent, hermetic seal, capable of withstanding high pressures, with a rapidity and certainty that lends itself readily to quantity production.

A further object of the invention is to provide a bellows tube with a head attached possessing the foregoing advantages.

Bellows are commonly made from brass and other alloys as well as sometimes from a single metal such for example as copper. When the metal employed is one that is readily weldable the present invention, as hereinafter explained, is carried out so as to weld or fuse the component parts of the joint into an integral unit. .When the metal employed, however, is one that is not readily weldable, the invention may be carried out with the use of hard solder, as silver solder or 'any other suitable alloy, that will form a fused integral joint in the manner hereafter described.

In order that the method and resultant article of the present ,invention ma be more readily understood reference is to e had to the appended drawings wherein the method has been illustrated more or less diagrammatically to show the manner in which the joint is formed, but it is to be expressly understood'that the drawings are for purposes of illustration only, and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for that purpose.

Referring to the drawings wherein the same reference characters are employed to designate corresponding parts in the several figures I Fig. 1 is a diagrammatic section to illustrate the parts of the joint before the same are fused; I

Fig. 2 is a corresponding section to illustrate the fusing of the joint;

Fig. 3 is a diagrammatic section to illus- {irate the completed joint on a completed belows' Fig. 4 is a fragmentary section showing an alternative form which the sections at the joint may take;

Fig. 5 is a fragmentary section showing the invention embodied in conjunction with a head which also serves as a reenforcement for the contiguous corrugation; and

Fig. 6 is a fragmentary section showlng the invention embodied by fusing radially directed flanges.

In accordance with the present invention the bellows tube 1, which as heretofore noted may be in the form of a cylindrical blank or a tube wherein the corrugations are partly formed or a completely corrugated tube, and which may be of any suitable size, cross sectional shape and thickness of metal, and which may be of any metal which is suitable IOU for the production of bellows, has mounted in the end thereof a head 2 which may be of any suitable metal, thickness, size and formation, and which is provided at its peripherv with an axially extending flange 3 which terminates in a portion 4 of reduced cross section. As shown, thehead 2 is provided with a tubular extension 5 having an aperture 6 such as is suitable for use where the corrugations are to beformed after the head is secured in the blank by the use of interior fluid pressure, but it is to be expressly understood that any other appropriate form or construction of head may be employed, with or without a filling opening or other aperture, and conforming to the use to which the completed bellows is to be put. The reduced edge 4 may be formed on the flange 3 1n any suitable way. Preferably, as shown in Fig. 1, the reduced edge is provided by forming an off-set in the flange, as this produces a joint of good appearance. An alternative construction, however, is shown in Fig. 4 wherein the flange 3 on the head 2 is made wedge-shaped in cross section so as to terminate in a reduced edge 4.

With the head 2 inserted in the end of the bellows tube 1 as shown in Fig. 1 or Fig. 4, a reenforcing ring 7 is mounted around the exterior of the bellows tube 1 in circumferential alignment with the flange 3. Ring 7 preferably has a similar or like cross section to the flange 3, so that it constitutes or affords a flange that terminates in a reduced edge 7 The outer diameter of the head and the inner diameter of the ring are preferably such that they snugly engage the bellows tube 1 at its inner and outer peripheries.

A welding flame, such for example as diagrammatically shown at 8 in Fig. 2, is then applied to the joint at the junction between the reduced edges 4 and 7 and the end of the tube 1 and passed progressively along the junction of these elements, so as to fuse or weld the tube 1 to the flange 2 and ring 7 the reduced edges 4 and 7 melting sufficiently to form a rigid integral hermetic joint between these elements. It will be appreciated that the welding flame can be produced and applied by any suitable apparatus known to the art.

Whether applied to the bellows tube before or after the formation of the corrugations, the completed bellows 9, as shown in Fig. 3, is provided with ahead that is rigidly and permanently secured thereto by an integral hermetic union, whichreenforces the end of the bellows tube interiorly and exteriorly thereof, because the end of the bellows tube is rigidly gripped and secured to the head and surrounding ring so that there is no danger of the tube breaking away from the head even though the interior of the bellows tube may be subjected to relatively high pressure.

If the metal employed is one that is not readily weldable, the joint as heretofore described can be effected by the use of any suitable hard solder, as silver solder or any other appropriate alloying metal applied to the junction between the end of the tube and the embracing head and ring, and then fused thereto by the application of a welding flame, the hard solder by its fusion integrating the end of the tube and the head and surrounding ring into an integral hermetic joint possessing the characteristics heretofore discussed.

Fig. illustrates the invention applied to a construction wherein the end corrugation is backed by the head. As here shown, the bellows 9 has its ends integrally attached to and between a head 2 and ring 10 by fusin the end of the tube to and between the refuced edges on said head and ring in the manner heretofore described, but in this embodiment the ring 10 takes the form of an annular disk having a radial dimension which approximates the radial depth of the corrugations, so that the ring 10 engages and backs the end corrugation 11 throughout its radial width. If desired, the ring 10 could extend radially beyond the corrugations so as to constitute a radially projecting flange, and by making this flange of suflicient stiffness and rigidity the reenforcing ring could thereby become a mounting ring.

While the embodiments so far illustrated employ an axially extending flange on the head the invention may be embodied with the use of a flange on the head which extends radially or at any other suitable angle to the axis of the tube, the tube end being suitably flanged or otherwise shaped to correspond. In Fig. 6, the bellows tube 12, which may be a blank tube or the lateral wall of a partly or completely formed bellows, is first provided with a radial flange 13 which is fused to a reduced edge 14 on the head 15 and a reduced edge 16 on a radially extending ring 17, as heretofore described. As before, the tube end is gripped between the aligned flanges on the head and ring surrounding the tube and is integrally united with and reenforced by said head and ring. I

It will, therefore, be perceived that a method of attaching a head to a bellows tube had been provided which is available for attaching a head to a blank or partly formed bellows or completed bellows; which is available for attaching a head to either or both ends of a blank; which is of such character that the metal of the tube is not injured as a result of the attachment; which is of such character that when used with a completed bellows the toughness and temper of the metal is not im aired because the brieflyapplied welding fl zime for fusing the end of the tube and the reduced edges of the head and ring does not heat the metal of the lateral wall suflicientlv to draw its temper since the relatively thick reinforcing ring and head shield the contiguous portion of the tube; which produces a joint sufficiently strong to withstand the pressures used in manufacturing bellows by fluid pressure; which avoids the complexities of mechanical joints and the difficulties heretofore experienced with the use of soft solder; which produces a strong, durable, permanent and integral joint that is easy to make; which does not require highly skilled labor or complicated apparatus; and which is expeditious and inexpensive to carry out so that it is readily applicable to quantity production in factory practice.

While certain embodiments of the invention have been illustrated and described with considerable detail, it is to be expressly understood that the invention is not restricted thereto as the method can be carried out in a variety of ways, the head and reenforcin rmg may take a variety of forms, the reduce edges can be formed in a variety of ways, and changes ma be made in the details of construction an arrangement and in the procedure followed without departing from the spirit of this invention. Reference is therefore to be had to the appended claims for a definition of said invention.

What is claimed is:

1. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substantially radial alignment with said head, the end of said bellows tube being fused to said head and said ring.

2. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substantially radial alignment with said head, said head and ring having relatively stifl' axially-extending flanges and the end of said bellows tube being fused to said flanges.

3. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substantially radial alignment with said'head, said head and ring having relatively stifl' axially-extending flanges which are reduced in cross section toward their extremities and the end of said bellows tube being fused to the extremities of said flanges.

4. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a rela tively thick reenforcing ring surrounding the end of the bellows tube and in substantially. radial alignment with said head, the end of said bellows tube being integrated by fusion with the aid of hard solder to said head and ring.

5. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substant ally radial alignment with said head, said ring having a backing flange and the end of said bellows tube being fused to said head and said ring.

6. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substantially radial alignment with said head, the end of said bellows tube being engaged between portions of said head and ring and being integrated therewith by fusion.

7. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcin g ring surrounding the end of the bellows tube and in substantially radial alignment with said head, the end of said bellows tube being engaged between portions of reduced cross sections on said head and ring an being integrated therewith by fusion.

8. A highly-flexible, deeply-corrugated metal bellows formed of relatively thin metal and provided with a relatively thick head within the end of the bellows tube and a relatively thick reenforcing ring surrounding the end of the bellows tube and in substantially radial alignment with said head, the end of said bellows tube being flanged and engaged between and fused to said head and ring.

9. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, embracing the end of the bellows tube between a relatively thick head and a relatively thick reenforcing ring and fusing the tube-end, head and ring into an integral joint.

10. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, embracing the end of the bellows tube between axially-extending sections of a relatively thick head and a relatively thick reenforcing ring and fusing the tube-end to said head and. ring to form an integral joint.

11. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, embracing the end of the bellows tube between flanges of a relatively thick head and a relatively thick reenforcing ring and fusing the tube-end to said flanges.

12. In a method of making highly flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin 5 metal of the bellows tube, embracing the end of the bellows tube between axially-extending flanges, having extremities of reduced cross section, of a relatively thick head and a relatively thick reenforcing rin and fusm ing the tube-end to the extremitles of said flanges.

13. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, embracing the end of the bellows tube between a relatively thick head and a relatively thick reenforcing ring and fusing with the aid of hard solder the tube-end, head and ring into an integral ]01Ilt.

14. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, positioning a relatively thick head within the end of the bellows tube, positioning around the exterior of the bellows a relatively thick reenforcing ring in circumferential alignment with said head and fusing said tube-end, head and ring into an integral joint.

15. In a method of making highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations bycold working in the relatively thin metal of the bellows tube positioning within the end of the bellows tube a relatively thick head having an axially-extending flange, surrounding the end of the bellows tube with a reenforcing ring having an ax ially-extending flange, and fusing said tube end to the flanges of said head and ring.

16. In a method of maln'ng highly-flexible bellows of relatively thin metal and which includes the forming of relatively deep corrugations by cold working in the relatively thin metal of the bellows tube, positioning within the end of the bellows tube a relatively thick head having an axially-extending flange which is reduced in cross section toward its extremity, surrounding the end Qf the bellows tube with a reenforcing ring having an axially-extending flange which is reduced in cross section toward its extremity, and fusing the tube-end to the extremities of said flanges.

In testimony whereof I have signed this specification.

JEAN v. GIESLER. 

